1. Technical Field
Embodiments of the present disclosure relate to a motor driven power steering system, and more particularly, to a motor driven power steering system which prevents floating and thereby absorbs shocks by covering a bearing installed on a worm shaft from the outside and at the same time enclosing the bearing.
2. Related Art
Generally, an electric power steering system, i.e., a motor driven power steering system (MDPS) is a system which assists a steering power with a motor power, not using a hydraulic pressure. To this end, the MDPS transmits a rotation force of a worm wheel to a gearbox to thereby assist a steering torque by having a motor which generates power under the control of an Electronic Control Unit (ECU), and a worm shaft which is rotated by a motor and the worm wheel in mesh therewith.
As described above, the MDPS uses the worm shaft and the worm wheel in mesh with each other, and therefore metallic noises, i.e., rattle noises occur as a result of a gap between gear teeth due to the abrasion of gear teeth and other various factors. Therefore there is a need of improvement.
The background technology is disclosed in Korean patent application publication No. 2009-0082821 under the title “a column assist type electric power steering system”, published on Jul. 31, 2009.